Underreamer



March 10, 1931. s. HlGHFlLL ET AL 1,795,367

UNDERREAMER Filed Feb. 26, 1927 2 Sheets-Sheet 2 I: i R P 15,

BY W

' ATTORNEY.

7.3 i 5 i a cross tio al fl w takenn "screw-threaded bore: 26, receives the upper denotes a reamer body having a longitudinal collar, and the expansion spring 18' forces Patented Mar. l0, p v I I umrso PATENT FFIQE- SAMUEL L.,1 E[IGHFILL, or WINFIELD, KANSAS, AND ROBERT P. MAYS, or CLEVELAND,

' Y OKLAHOMA 1 UNDER-REAMER Application filed Februar .26, 1927. Serial 1%. 171,251.

"'Our invention relates to welld-rilling tools A mandrel is disposed in the bore 6 of and more particularly. tov improvements in the reamer body having its lower end dis: under-reamers. V w 3 posed intermediate the inner faces ofthe cut- 'Itis an ohjectol our invention to-provide ters, which are provided with longitudinal v 5 an underreamer having-a releasablelocking grooves 16 to receive themandrel andthe means associated with the expansion means upper ends of the cutters contact. with the] for-the cutters, whereby the cutters and. exmandrel-which serves as a fulcrum for. the pansion means will befirmly maintained in cutters which automatically move to a 001-. operating position and yet may be readily lapsed position when the expansion Wedge 17,

10 disassembled and which is especially adapted connected to the lower end of the mandrel for use with the under-reamer shown in our is withdrawn. This construction is identical co-pending application, filed January '11, With the construction shown and claimed in 1927 Serial1\Tu b r 160,427; 7 v our co-pending application, above referred A further'objectof the invention is to proto and is merely shown for the sake Of CllT- 15 vied a device of the ahove mentioned char- I less understanding the presentinvention acter which is simpleand'durable in construcnd it is to be understood that the showing tion, reliable and efiicientin operation and inof this construction is not intended to limit x iv t n f t 1 "f theu'se of'the present invention to a'conoth bj t d, d t of th -i struction ofthis character, as the same may 0 venti'on will be apparent during thecourse of e used wIthfC l a u typ thefollowing. description. Referring more particularly to our-present.

f In the accompanying drawings, forming a lnventlon an expansionspring 18ismounted part of this specification and in whichlike 0n the .malldrel 15 Within bore of the numerals are employed to designate like parts l' mer' body having its lower end seated on throu ho t th same, I the shoulderl9 at the lower end of the bore "Fig. 1 is}; longitudinal ctio al i of and its upper end bearing against the clutch an'under-reamer embodying our invention, Collar 20, slidably mount-ed on theuppeir en Fig. 2, is anenlarged longitudinal sectional 9 e m ndrel. A key 21, fitted 1n the open View of the same, I 1ng 22, 1n the s de ofthe collar enters a longi- 3 1 a vi i il t rFi g howi'f tud1nal keyway 22 formed 1n the mandrel, 80 th d l d d, it connecting the collar and'mandrel together.

F ig.4, is a detailjperspective view of the e l' m upp r end of the mandrel screw-threaded as at'23 and terminates in a clutchmechanism showing the fparts in sep- I reduced square head 24. A stud, 25 having a arate relation, and,"

lines 55 of Figi3. 1 I a end-of the mandrel and its lower endis pro In'the-drawings,.wherein.for the-pur s 'vided with a seriesof spaced notches 27, of illustratiomlwe haveshown apreferred adapted iecelve. h 11111111980? i 1 embodi t. f ii v ntion, the numeral 5 formed around the upper edge oftheclutch g0 .bore 6, enlarged'at' its lower end to provide the'clutch 'collar'upwardly'intotight engagea socket 7, "to receive the I shanks 8 of the nient with the notches of the stud, at the same rockahle cutters 9,which are suspended from 611116 eliciting an upward thrust upon the the wall of the socket by-lugg 10,'ad t d t mandrel, causing the wedge block to expand 4 45 fit slots 11 formed in the wall. The upper and firmly hold the cutters in operative posiend of the body isprovided with atapered 'tion. I screw-threaded recess 12 to receive the screw- The trip mechanism for holding the threaded nipple 13 depending fromthe cap mandrel'depressed while inserting the reamer V50 14, by means of which the reamer is'connected into the well hole, consists of a cross bar 29 with the usual string of drillingtools. which" extends transversely through openings in the stud 25, and is provided centrally of its lower edge with a recess 31, to receive the square head 24. of the mandrel when the latter is screwed into the stud, locking the bar against undue transverse move ment. The bar moves longitudinally of the body in the longitudinal slots 32, extending between the bore of the body and the longitudinal grooves 33, formed in opposite sides of the body. A trip 34 is mounted on each end of the cross bar being slidably connected therewith by transverse pins 35, extending through slots 36 in the bar. The trips are movable longitudinally in the grooves 33 and the surface of the grooves at their lower portions are on a plane nearer the longitudinal axis of the body, than the upper portions, so that when the trips are seated in the lower ends of the grooves they will lie within the circumference of the body. The grooves are of such length that the wedge 17 may be withdrawn to clear the bottom of the cutters to permit turning of the mandrel. hen the wedge is withdrawn, for the purpose of removing the mandrel, it is held in this position by a removable pin 34 extending transversely of the body, which intersects the bore Sand serves as a stop for the upper end of the stud.

From the foregoing, it is seen that the clutch collar is held in tight engagement with the stud, through the tension of the spring, releasably locking the mandrel against rotary movement. To remove the cutters from the socket it is necessary to first remove the mandrel and when the mandrel is withdrawn, so the wedge clears the bottom of the cutters, the turning of the mandrel under pressure will release the clutch, permitting the mandrel to be unscrewed from the stud and with drawn from the body, thereby permitting ready removal. of the cutters. Also the removal of the mandrel will release the cross bar of the trip mechanism and upon removal of one of the trips, the mechanism may be readily disassembled if desired.

It is to be understood that the form of our invention herewith shown and described is to be taken as a preferred example of the same and that certain changes in the shape, size and arrangement of the parts may be made without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described our invention, we claim I 1. A tool of the character described comprising a body, movable cutters, actuating means for said cutters and a clutch associated with said actuating means for normally holding it against removal, said actuating means being releasable upon rotation under pressure.

2. A tool of the character described comprising a body, movable cutters, actuating means for said cutters removably mounted within said body and a clutch associated with said actuating means normally holding same against removal, said actuating means being releasable upon rotation under pressure.

3. A tool of the character described comprising a body, movable cutters, a trip mechanism, actuating means for said cutters removably connected with said trip mechanism and a clutch normally holding said actuating means against removal, said clutch being releasable upon rotation of the actuating means under pressure.

4:. A tool of the character described comprising abody, movable cutters, a trip mechanism, spring controlled actuating means for said cutters removably connected with said trip mechanism and a clutch carried by said actuating means for locking said means against removal, said clutch being releasable upon rotation of the actuating'means under pressure.

5. A tool of the character described comprising a body, movable cutters, actuating means for said cutters removably mounted in said body, a clutch for normally locking said actuating means against removal and a spring for controlling said actuating means and clutch, said actuating means being releasable upon rotation under pressure.

6. A tool of the character described com prising a body, movable cutters, expanding means for said cutters detachably mounted in said body, a clutch collar for normally looking said expanding means against detachment slidably' mounted on and connected with said expanding means and a spring for controlling said expanding means and clutch collar.

7. A tool of the character described comprising a body, movable cutters, expanding means for said cutters mounted in said body, a clutch member slidably mounted in said body adapted to detachably receive the upper end of said expanding means, a clutch collar slidably mounted on and connected with said expanding means adapted to co-act with said clutch member and a spring for controlling said expanding means and clutch collar.

8. A tool of the character described comprising a body, movable cutters, a stud slidably mounted in said body, expanding means for said cutters mounted in said body and detachably connected with said stud, a clutch collar slidably mounted on and connected with said expanding means adapted to co-act with said stud and a spring ior controlling said expanding means and clutch collar.

. 9. A tool of the character described comprising a body, movable cutters, a stud slidably mounted in said body, a trip mechanism consisting of a cross bar extending transversely through said body and stud, expanding means for said cutters mounted in said body and detachably connected with said stud, a clutch collar slidably mounted on said expanding means adapted to co-act with said stud to normally hold said expanding means against detachment, and a spring for controlling said expanding means and clutch col- 10. A tool of the character described comprising a body, movable cutters, a trip mechanism, actuating means for said cutters and a clutch detachably connecting said actuating means with said trip mechanism, said clutch being releasable upon rotation of the actuating means under pressure.

11. A tool of the character described comprising a body, movable cutters, a clutch member slidably mounted in saidv body, a trip mechanism consisting of a cross bar extending transversely through said body and clutch member having a notch in its lower edge, means for actuating said cutters detachably connected with said clutch member and having engagement With said notch, anda clutch collar carried by said actuating means adapted to normally hold said means against removal.

In testimony whereof We aflix our signatures.

SAMUEL L. HIGHFILL. ROBERT P. MAYS. 

